This invention relates to a fiber optic cable distribution frame system particularly well suited for use for high density fiber optic cable applications.
In the telecommunications industry there are numerous locations where a significant amount of fiber optic cable must be routed within a facility or from one facility to another. The number of fibers may be great and the fibers must all be handled with great care to avoid damage to the fiber optic cable, which hinders its performance. For instance, it is important to maintain a minimum bend radius to protect the fiber optic cables. A minimum bend radius may for example be one and one-half inches, or it may be thirty millimeters (30 mm).
Fiber optic cable distribution frames, bays or panels are generally utilized to provide termination, cross-connect, splice, patch and storage interface between fiber optic cables that lead to user installations.
These bays typically include high density fiber optic cable distribution frameworks which include fiber-optic cross connection and/or patching functions or features. Typically, but not always, outside plant (OSP) fiber optic cables are routed into the facility and need to be connected to equipment or to other fiber optic cables.
The increase in use of telecommunication fiber optic cables has. brought with it the need to increase the capacity of existing facilities, and the need to increase the density of connections or inter-connections per given area. As density increases and the vertical spacing between fiber optic connectors decreases, the management of the fiber optic cable becomes more and more difficult due to the geometrical limitations imposed by the decreased spacing of the fiber optic connectors and the management and routing of the fiber optic cables.
In fiber optic cable distribution frameworks and applications, the management of the fiber is important, especially in applications which include a higher density of fiber optic cables. The amount of cable being routed through a typical distribution frame can be very great, and to the extent the design and configuration of the distribution frame (as well as the way fiber is routed through the distribution frame) can minimize the amount of fiber optic cable needed, the cost and weight of the fully loaded distribution frame can be lowered. This also increases the efficiency of the management of the fiber optic cable.
In a typical prior art application, one example of which is illustrated in FIG. 1, a distribution frame 100 may include one or more fiber optic assemblies 101 mounted on a first side 100a of the frame 100 and one or more fiber optic assemblies 102 mounted on a second side 100b of the frame 100. The fiber optic cable may be routed from the first side 100a to the fiber support area 111, and then to the second side 100b of the framework. A first vertical fiber pathway 104 is created between the one or more first fiber optic assemblies 101 and the first partition wall 105, and a second vertical fiber pathway 109 is created between the one or more second fiber optic assemblies 102 and the second partition wall, 110.
The first fiber pathway 104 generally receives fiber optic cables 103 from the one or more first fiber assemblies 101, and the second fiber pathway 109 may be disposed to receive fiber optic cables from the central fiber support area 111, and facilitates the routing of the fiber optic cables 14 to the one or more second fiber assemblies 102. A typical arrangement includes a generally vertically oriented plurality of fiber supports secured between the first partition wall 105 and the second partition wall 110. The fiber supports are adapted to receive one or more fiber optic cables.
In these typical prior art distribution frameworks, the fiber optic cable from the first side of the framework is routed downwardly around the entire first partition wall 105 to or near the bottom of the framework, then routed Ado upward through part of the fiber support area 111 in the direction of arrow 107, around a fiber support 106, downward in the direction of arrow 108 to below the second partition wall 110, and then up to the desired location to a fiber optic connector assembly 102 on the second side 100b of the framework. It is generally desirable to minimize the number of different fiber lengths for a given distribution frame, and it is preferable to only have one length.
As can be seen, these prior art distribution frameworks require a higher than necessary amount of cable because the fiber optic cable is typically cut to a standard length, and that standard length must be longer because it must accommodate the longest run of fiber. In a typical prior art system, the standard fiber may be approximately five and one-half meters long, which in the case of a typical five hundred seventy-six termination framework, requires five hundred seventy-six fiber optic cable patch cords at that length. From these figures, it will be appreciated the savings that could be incurred if the average length of the fiber optic cable is reduced.
In an embodiment of this invention, one or more intermediate transverse fiber pathways are provided between the first side 100a and the fiber support area 111, and also provided between the second side 100b of the framework 100, and the fiber support area 111. The intermediate transverse fiber pathways fill a long felt need and provide intermediate fiber pathways for the routing of fiber optic cables, and reduce the necessary length of the standard fiber optic cables needed for the distribution frame. In the case where intermediate fiber optic cable pathways are provided at or near the mid-point of the fiber pathway wall, the necessary length of standard fiber optic cable may be reduced, for example from five and one-half meters to four and one-half meters. In embodiments of this invention in which fiber optic cable from the top section of the first side 100a are only routed to the fiber support area 111 and then to the top section of the second side 100b, the standard fiber optic cable length may be as low as two and one-half meters.
This results in better cable management and reduced fiber optic cable costs.